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Information on EC 1.14.18.1 - tyrosinase and Organism(s) Solanum tuberosum and UniProt Accession Q41428

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EC Tree
IUBMB Comments
A type III copper protein found in a broad variety of bacteria, fungi, plants, insects, crustaceans, and mammals, which is involved in the synthesis of betalains and melanin. The enzyme, which is activated upon binding molecular oxygen, can catalyse both a monophenolase reaction cycle (reaction 1) or a diphenolase reaction cycle (reaction 2). During the monophenolase cycle, one of the bound oxygen atoms is transferred to a monophenol (such as L-tyrosine), generating an o-diphenol intermediate, which is subsequently oxidized to an o-quinone and released, along with a water molecule. The enzyme remains in an inactive deoxy state, and is restored to the active oxy state by the binding of a new oxygen molecule. During the diphenolase cycle the enzyme binds an external diphenol molecule (such as L-dopa) and oxidizes it to an o-quinone that is released along with a water molecule, leaving the enzyme in the intermediate met state. The enzyme then binds a second diphenol molecule and repeats the process, ending in a deoxy state . The second reaction is identical to that catalysed by the related enzyme catechol oxidase (EC 1.10.3.1). However, the latter can not catalyse the hydroxylation or monooxygenation of monophenols.
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Solanum tuberosum
UNIPROT: Q41428
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The taxonomic range for the selected organisms is: Solanum tuberosum
The expected taxonomic range for this enzyme is: Eukaryota, Bacteria, Archaea
Reaction Schemes
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L-tyrosine
+
O2
=
dopaquinone
+
H2O
+
=
+
2
L-dopa
+
O2
=
2
dopaquinone
+
2
H2O
2
+
=
2
+
2
Synonyms
tyrosinase, monophenolase, oxygen oxidoreductase, phenol oxidases, murine tyrosinase, melc2, o-diphenol oxidase, monophenol oxidase, met-tyrosinase, jrppo1, more
SYNONYM
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
monophenol, o-diphenol:oxygen oxidoreductase
-
polyphenol oxidase
-
catechol oxidase
-
-
-
-
catecholase
-
-
-
-
chlorogenic acid oxidase
-
-
-
-
chlorogenic oxidase
-
-
-
-
cresolase
-
-
-
-
Diphenol oxidase
-
-
-
-
dopa oxidase
-
-
-
-
monophenol dihydroxyphenylalanine:oxygen oxidoreductase
-
-
-
-
monophenol monooxidase
-
-
-
-
monophenol oxidase
-
-
-
-
monophenol, dihydroxy-L-phenylalanine oxygen oxidoreductase
-
-
-
-
monophenolase
-
-
-
-
N-acetyl-6-hydroxytryptophan oxidase
-
-
-
-
o-diphenol oxidase
-
-
-
-
o-diphenol oxidoreductase
-
-
-
-
o-diphenol:O2 oxidoreductase
-
-
-
-
o-diphenol:oxygen oxidoreductase
-
-
-
-
o-diphenolase
-
-
-
-
phenol oxidase
-
-
-
-
phenolase
-
-
-
-
polyaromatic oxidase
-
-
-
-
polyphenol oxidase
polyphenolase
-
-
-
-
pyrocatechol oxidase
-
-
-
-
tyrosinase
-
-
-
-
tyrosine-dopa oxidase
-
-
-
-
REACTION TYPE
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
redox reaction
-
-
-
-
oxidation
-
-
-
-
reduction
-
-
-
-
SYSTEMATIC NAME
IUBMB Comments
L-tyrosine,L-dopa:oxygen oxidoreductase
A type III copper protein found in a broad variety of bacteria, fungi, plants, insects, crustaceans, and mammals, which is involved in the synthesis of betalains and melanin. The enzyme, which is activated upon binding molecular oxygen, can catalyse both a monophenolase reaction cycle (reaction 1) or a diphenolase reaction cycle (reaction 2). During the monophenolase cycle, one of the bound oxygen atoms is transferred to a monophenol (such as L-tyrosine), generating an o-diphenol intermediate, which is subsequently oxidized to an o-quinone and released, along with a water molecule. The enzyme remains in an inactive deoxy state, and is restored to the active oxy state by the binding of a new oxygen molecule. During the diphenolase cycle the enzyme binds an external diphenol molecule (such as L-dopa) and oxidizes it to an o-quinone that is released along with a water molecule, leaving the enzyme in the intermediate met state. The enzyme then binds a second diphenol molecule and repeats the process, ending in a deoxy state [7]. The second reaction is identical to that catalysed by the related enzyme catechol oxidase (EC 1.10.3.1). However, the latter can not catalyse the hydroxylation or monooxygenation of monophenols.
CAS REGISTRY NUMBER
COMMENTARY hide
9002-10-2
not distinguished from EC 1.10.3.1
SUBSTRATE
PRODUCT                       
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate) hide
LITERATURE
(Substrate)
COMMENTARY
(Product) hide
LITERATURE
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
(+)-catechin hydrate + 1/2 O2
?
show the reaction diagram
-
-
-
?
(-)-epicatechin + 1/2 O2
?
show the reaction diagram
-
-
-
?
caffeic acid + 1/2 O2
caffeoyl quinone + H2O
show the reaction diagram
-
-
-
?
D-dopa + 1/2 O2
D-dopaquinone + H2O
show the reaction diagram
tyrosinase oxidizes L- and D-forms with similar rate
-
-
?
D-tyrosine + O2 + AH2
D-dopa + H2O + A
show the reaction diagram
tyrosinase oxidizes L- and D-forms with similar rate
-
-
?
DL-dopa + 1/2 O2
DL-dopaquinone + H2O
show the reaction diagram
tyrosinase oxidizes L- and D-forms with similar rate
-
-
?
DL-tyrosine + O2 + AH2
DL-dopa + H2O + A
show the reaction diagram
tyrosinase oxidizes L- and D-forms with similar rate
-
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
tyrosinase oxidizes L- and D-forms with similar rate
-
-
?
L-tyrosine + O2 + AH2
L-dopa + H2O + A
show the reaction diagram
tyrosinase oxidizes L- and D-forms with similar rate
-
-
?
p-cresol + O2
4-methylpyrocatechol + H2O
show the reaction diagram
relatively well oxidized
-
-
?
p-tyrosol + O2 + AH2
2-(3,4-dihydroxyphenyl)ethanol + H2O + A
show the reaction diagram
relatively well oxidized
-
-
?
phenol + O2 + AH2
catechol + H2O + A
show the reaction diagram
-
-
-
?
pyrocatechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
?
pyrogallol + 1/2 O2
?
show the reaction diagram
-
-
-
?
tyramine + O2
4-(2-aminoethyl)cyclohexa-3,5-diene-1,2-dione + H2O
show the reaction diagram
-
-
-
?
(-)-epicatechin + O2
?
show the reaction diagram
-
119% activity at 2.5 mM substrate concentration
-
-
?
2 catechol + O2
2 1,2-benzoquinone + 2 H2O
show the reaction diagram
-
100% activity at 10 mM substrate concentration
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone + H2O
show the reaction diagram
-
highest activity, 183% activity at 10 mM substrate concentration
-
-
?
caffeic acid + O2
caffeoyl quinone + H2O
show the reaction diagram
-
31% activity at 2.5 mM substrate concentration
-
-
?
DL-DOPA + O2
dopaquinone + H2O
show the reaction diagram
-
39% activity at 2.5 mM substrate concentration
-
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
-
-
-
?
L-DOPA + O2
dopaquinone + H2O
show the reaction diagram
-
-
-
-
?
L-tyrosine + O2
L-DOPA + H2O
show the reaction diagram
-
very low activity, 6% activity at 2.5 mM substrate concentration
-
-
?
L-tyrosine + O2 + AH2
L-dopa + H2O + A
show the reaction diagram
-
-
-
-
?
p-cresol + O2
?
show the reaction diagram
-
20% activity at 2.5 mM substrate concentration
-
-
?
pyrogallol + O2
?
show the reaction diagram
-
92% activity at 10 mM substrate concentration
-
-
?
additional information
?
-
NATURAL SUBSTRATE
NATURAL PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate) hide
LITERATURE
(Substrate)
COMMENTARY
(Product) hide
LITERATURE
(Product)
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
additional information
?
-
-
the partially purified enzyme has both cresolase and catecholase activity. Activity is lower toward monophenols than diphenols
-
-
?
INHIBITOR
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
IMAGE
2-mercaptoethanol
-
4-butylbenzoic acid
-
reversible and noncompetitive inhibitor
4-heptylbenzoic acid
-
reversible and noncompetitive inhibitor
4-hexylbenzoic acid
-
reversible and noncompetitive inhibitor
4-octylbenzoic acid
-
reversible and noncompetitive inhibitor
4-pentylbenzoic acid
-
reversible and noncompetitive inhibitor
4-propylbenzoic acid
-
reversible and noncompetitive inhibitor
ascorbic acid
-
effective inhibitor, 99% inhibition at 1 mM
benzoic acid
-
9% residual activity at 10 mM
borax
-
71% residual activity at 10 mM
CaCl2
-
69% residual activity at 10 mM
Citric acid
-
10% residual activity at 10 mM
EDTA
-
57% residual activity at 10 mM
L-cysteine
-
complete inhibition at 1 mM
N-acetyl-L-cysteine
-
1% residual activity at 1 mM
potassium sorbate
-
78% residual activity at 10 mM
Sodium metabisulfite
succinic acid
-
35% residual activity at 10 mM
ACTIVATING COMPOUND
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
IMAGE
SDS
-
172% activity at 10 mM
additional information
-
activity depends on buffer system: highest activity in citrate-phosphate buffer
-
KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
IMAGE
5.39
L-Dopa
-
-
additional information
additional information
-
kinetic parameters for free and immobilized enzymes, determined according to the Michaelis-Menten equation, show a lower Km value for PPO-MAC400 than for the free enzyme, indicating higher affinity towards substrate, while PPO-MAC200 exhibits a higher Km value
-
Ki VALUE [mM]
INHIBITOR
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
IMAGE
1.62
KCl
-
competitive vs. L-dopa
1.82
NaCl
-
competitive vs. L-dopa
IC50 VALUE [mM]
INHIBITOR
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
IMAGE
0.18
4-butylbenzoic acid
Solanum tuberosum
-
in 50 mM PBS (pH 6.8), temperature not specified in the publication
0.075
4-heptylbenzoic acid
Solanum tuberosum
-
in 50 mM PBS (pH 6.8), temperature not specified in the publication
0.106
4-hexylbenzoic acid
Solanum tuberosum
-
in 50 mM PBS (pH 6.8), temperature not specified in the publication
0.047
4-octylbenzoic acid
Solanum tuberosum
-
in 50 mM PBS (pH 6.8), temperature not specified in the publication
0.152
4-pentylbenzoic acid
Solanum tuberosum
-
in 50 mM PBS (pH 6.8), temperature not specified in the publication
0.213
4-propylbenzoic acid
Solanum tuberosum
-
in 50 mM PBS (pH 6.8), temperature not specified in the publication
SPECIFIC ACTIVITY [µmol/min/mg]
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
additional information
pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
6 - 6.5
pH-optimum
7
enzyme activity assay at
5
-
the optimum conditions for immobilization of PPO onto MAC400 and MAC200 are temperature 40°C, pH 5 and at PPO activity equal to 300000 U/l
additional information
-
activity depends on buffer system: highest activity in citrate-phosphate buffer
pH RANGE
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
5.5 - 8.5
active at this pH-range
4.5 - 7.5
-
-
5 - 8
-
PPO is immobilized onto MAC400 and MAC200 at various enzyme activities 50000, 100000, 200000, 300000 U/l, at pH 5-8, and at temperature ranging from 10 to 40°C
TEMPERATURE OPTIMUM
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
25
enzyme activity assay at
40
-
the optimum conditions for immobilization of PPO onto MAC400 and MAC200 are temperature 40°C, pH 5 and at PPO activity equal to 300000 U/l
TEMPERATURE RANGE
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
10 - 40
-
PPO is immobilized onto MAC400 and MAC200 at various enzyme activities 50000, 100000, 200000, 300000 U/l, at pH 5-8, and at temperature ranging from 10 to 40°C
ORGANISM
COMMENTARY hide
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
tyrosinases from apple, potato, the white rot fungus Pycnoporus sanguineus, the filamentous fungus Trichoderma reesei and the edible mushroom Agaricus bisporus are compared for their biochemical characteristics
UniProt
Manually annotated by BRENDA team
SOURCE TISSUE
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
SOURCE
UNIPROT
ENTRY NAME
ORGANISM
NO. OF AA
NO. OF TRANSM. HELICES
MOLECULAR WEIGHT[Da]
SOURCE
SEQUENCE
LOCALIZATION PREDICTION?
Q41428_SOLTU
599
0
67526
TrEMBL
-
MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
45000
determined by SDS-PAGE
pH STABILITY
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
2.5 - 3.5
-
the enzyme is most unstable at pH 2.5-3.5 retaining less than 10% of original activity after 2 h
712619
6 - 7.5
-
more than 50% activity is retained during storage for 72 h at pH 6.0-7.5
712619
TEMPERATURE STABILITY
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
20 - 80
-
residual activity is higher than 50% after incubation at 20°C for 72 h, at 30°C for 48 h, at 40°C for 24 h, at 50°C for 2 h, and at 60°C for 15 min. Heating at 80°C for 15 min inactivates the enzyme
PURIFICATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
ammonium sulfate precipitation and Sephadex G-100 gel filtration
-
ammonium sulfate precipitation, phenyl Sepharose column chromatography, ion exchange chromatography, and hydroxyapatite column chromatography
-
REF.
AUTHORS
TITLE
JOURNAL
VOL.
PAGES
YEAR
ORGANISM (UNIPROT)
PUBMED ID
SOURCE
Malkin, B.D.; Thickman, K.R.; Markworth, C.J.; Wilcox, D.E.
Kull, F.J.: Inhibition of potato polyphenol oxidase by anions and activity in various carboxylate buffers (pH4.8) at constant ionic strength
J. Enzyme Inhib.
16
135-145
2001
Mushroom, Solanum tuberosum
Manually annotated by BRENDA team
Kennedy, L.J.; Selvi, P.K.; Padmanabhan, A.; Hema, K.N.; Sekaran, G.
Immobilization of polyphenol oxidase onto mesoporous activated carbons --isotherm and kinetic studies
Chemosphere
69
262-270
2007
Solanum tuberosum
Manually annotated by BRENDA team
Selinheimo, E.; NiEidhin, D.; Steffensen, C.; Nielsen, J.; Lomascolo, A.; Halaouli, S.; Record, E.; OBeirne, D.; Buchert, J.; Kruus, K.
Comparison of the characteristics of fungal and plant tyrosinases
J. Biotechnol.
130
471-480
2007
Malus domestica, Trametes sanguinea, Trichoderma reesei, Agaricus bisporus (O42713), Solanum tuberosum (Q41428)
Manually annotated by BRENDA team
Lin, M.; Ke, L.; Han, P.; Qiu, L.; Chen, Q.; Lin, H.; Wang, Q.
Inhibitory effects of p-alkylbenzoic acids on the activity of polyphenol oxidase from potato (Solanum tuberosum)
Food Chem.
119
660-663
2010
Solanum tuberosum
Manually annotated by BRENDA team
Ni Eidhin, D.; Degn, P.; Obeirne, D.
Characterization of polyphenol oxidase from rooster potato (Solanum tuberosum cv Rooster)
J. Food Biochem.
34
13-30
2010
Solanum tuberosum
Manually annotated by BRENDA team